package com.leetcode.tag.daily;

/**
 * 官方:合并两个有序链表
 */
public class GMergeTwoSortedLists {
  /**
   * 作者：LeetCode-Solution
   * 链接：https://leetcode-cn.com/problems/merge-two-sorted-lists/solution/he-bing-liang-ge-you-xu-lian-biao-by-leetcode-solu/
   * 来源：力扣（LeetCode） 著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。
   */
  public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
    if (l1 == null) {
      return l2;
    } else if (l2 == null) {
      return l1;
    } else if (l1.val < l2.val) {
      l1.next = mergeTwoLists(l1.next, l2);
      return l1;
    } else {
      l2.next = mergeTwoLists(l1, l2.next);
      return l2;
    }
  }

  public class ListNode {
    int val;
    ListNode next;

    ListNode(int x) {
      val = x;
    }
  }
}
